| OCR Text |
Show 1874.] MR. E. C. REED ON CHILIAN COLEOPTERA. 49 Horn, and has, as far as I can see, every right to it; but it seems that in Patagonia the Andes disappear, and there is therefore no definite boundary. Again, on the north, Dr. Philippi found during his journey in the desert of Atacama that the great South-American « backbone was utterly dislocated there; and in place of a continuous chain with a well defined water-parting, he found a plateau of considerable height and isolated mountain cones; and as no rain falls just there, the dividing line cannot be found. One zoological region, however, which I may call Chili Proper, is very well defined,-the desert of Atacama, in which a dozen species of Coleoptera have not yet been found, being the northern boundary (24° S.), the archipelago of Chonos (about 45° S.) the southern, the Pacific the western, and the snowy Andes the eastern. The interruption of the Andean chain in Atacama has no importance with regard to the insect fauna, as no species appears to be able to cross that arid region. W e have therefore to deal with a long narrow strip of land, extending twenty-one degrees from north to south, with a width of but two and a half degrees in its widest part, and presenting more climatic peculiarities than, probably, any other part of the world of equal extent. In addition to the Andes, a coast-range runs through Chili from north to south, with many peaks from 4000 to 5000 feet in height. Between the Andes and the coast-range lies the " central plain" of Chili, with a height above the sea of 1800 feet at Santiago, thence southwards sloping down to the sea-level at Port Montt, and rising northwards to form the high tablelands of Atacama and Bolivia. With regard to climate, most travellers agree that it rains sometimes in the desert of Atacama; but a difference of opinion exists about the amount; some state that it rains there nearly every year, while Dr. Philippi states that it probably has but few showers in a century. About Valdivia, on the other hand, little difference of opinion can exist, as a week of dry weather is an exception to the rule. About one hundred and twenty inches may be taken as the average yearly rainfall of Valdivia. * This abundant rainfall in the south naturally produces a varied and rich flora; but, strange to say, Chili is far from rich in insects, either in species or individuals. About four thousand species of vascular plants are recorded, while the Coleoptera scarcely pass two thousand species; and many of these appear to be very rare. Gay, the author of the ' Historia Fisica y Politica de Chile,' after collecting assiduously for many years, described only about 1500 species of insects of all orders; and in this number he included all previous descriptions that he was acquainted with, and introduced many insects erroneously into the Chilian Fauna. On m y arrival in Chili, in 1866, some 3000 species of all orders were known; and even now they scarcely reach 4000, and new species are not as easily obtained as formerly. Owing to the gradual transition of climate in Chili it is difficult to divide the country into districts or "centres;" but if this latter PROC. ZOOL. Soc-1874, No. IV. 4 |
